What happens when we all become Buddhas?

If we have infinite lifetimes to become enlightened wouldn't it follow that we'll all eventually get there? What happens then? I've heard Thurman describe a buddhaverse/buddha-land as a sort of food fight where everyone is trying to throw happiness/good-will or something like that at each other. Does this just happen forever, or is there something like a cycle that happens where we get bored and choose to forget our own buddha nature for for the drama or entertainment of being in such a situation and eventually coming back to our real identity and reality?